<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>布局容器</title>
    <script src="jquery-3.4.1.js"></script>
    <script src="bootstrap.js"></script>
    <link rel="stylesheet" href="bootstrap.css">
    <style>
        div[class^="container"]{
            border: 1px solid #000;
        }
    </style>



</head>
<body>
<!--居中显示，两边留白-->
<div class="container">container</div>
<!--占满整个屏幕-->
<div class="container-fluid">container-fluid</div>

<div><iframe src="栅格系统.html"></iframe></div>
</body>
</html>